The invention concerns a sausage casing gripping apparatus for use with gathered concertinaed sausage casings and a sausage filling machine. The apparatus includes two gripping elements, in other words a first and second gripping element, which are movable relative to each other and which grip the concertinaed sausage casing by a reduction in the intermediate space between the gripping elements and which release the concertinaed sausage casing by an expansion of the intermediate space. The apparatus further includes a drive device for moving at least one of the gripping elements, and at least one lever element, in other words a first lever element and optionally a second lever element, for coupling the drive device to at least one gripping element.
Such sausage casing gripping apparatuses are used with sausage filling machines to apply gathered (concertinaed) sausage casings from a magazine onto a filling tube of the filling machine.
DE 40 14 410 C2 discloses a magazine apparatus for sausage casings comprising two gripper halves for gripping a sausage casing. The gripper halves extend in a substantially horizontal direction and are fixed to stirrups. The stirrups are suspended on carriages which are mounted on and displaceable along two guide shafts. The carriages allow rotary movement about the guide shafts on which they are mounted, whereby the gripper halves can be moved in a direction transverse to the length of the sausage casings. The gripper halves can also be moved towards each other for closing and away from each other for opening. Each gripper half is arranged laterally and is directed towards the sausage casing. The gripping surface of each gripper half comprises two halves arranged at approximately a right angle, and each gripper half makes tangential contact with the sausage casing when the gripper halves close. Accordingly, the gripper halves are designed in the manner of a prism. A support device is arranged beneath the gripper halves substantially in alignment with the central plane of a feed shaft. Retaining plates provide that only one respective sausage casing is disposed in the gripping region of the gripper halves. To receive a sausage casing the gripper halves are rotated outwardly by rotation of the carriages about the guide shafts so that the spacing between the gripper halves is increased. A sausage casing is then dropped onto the support device from the feed shaft. The gripper halves are rotated towards the sausage casing lying on the support device and enclose the sausage casing over its entire length.
Given the dimensions of the feed shaft and the gripper halves, the magazine apparatus is always limited to known types of sausage casing. Sausage casings of a larger diameter than the width of the feed shaft cannot be processed with that magazine apparatus and the gripper halves. The gripper halves would inadequately grip sausage casings of excessively large diameter so that the sausage casings suffer damage while being processed. Sausage casings of excessively small diameter also cannot be processed by this apparatus because the sausage casings cannot be adequately gripped by the gripper halves.
DE 30 19 981 also discloses a magazine apparatus for sausage casings, used for applying a casing onto a packing tube to receive a plastically deformable material such as sausage or cheese.
DE 10 2008 026 095 A1 discloses an apparatus for applying a casing onto a filling tube to produce foodstuff products such as sausages. The apparatus includes a pair of reciprocatable bars driven by a drive mechanism such as a conventional compressed air cylinder unit. An enclosing clamping device is formed by two holding elements of rectangular shape, arranged opposite to each other on either side of the casing. In the closed condition the enclosing clamping device forms a substantially quadrangular space. The bars are arranged substantially horizontally and are moved apart to place the sausage casing in the quadrangular space formed by the holding elements in the closed condition.
DE 30 24 509 discloses a sausage filling machine having a sausage casing gripping apparatus, which involves a comparable working principle. Consequently, the invention in accordance with DE 30 24 509 suffers from the same disadvantages.
DE 30 19 981 discloses another magazine apparatus for sausage casings having a substantially vertical guide shaft which includes two shaft walls. The spacing between the shaft walls can be adjusted symmetrically relative to the vertical central plane of the guide shaft by a spindle which engages the shaft walls with oppositely-threaded screwthreads. The guide shaft is closed at the lower end by a shaft floor of strip-like configuration arranged so that a sausage casing resting on the shaft floor is oriented toward the center of the packing tube. The apparatus in accordance with DE 30 19 981 can be adapted to different sausage casing diameters only with increased complication and expenditure. In order to adapt the apparatus to such sausage casings, the guide shaft must first be emptied of all sausage casings. In addition, the guide shaft can only be adjusted manually.
DE 43 23 128 T2 discloses an apparatus having a supply container for individually separating and applying a concertinaed sausage casing onto a filling tube. The apparatus includes a conveyor belt of V-shaped cross-section, on which the concertinaed sausage casings from the supply container are placed. A height-adjustable centering device with a flat cross-sectional surface then permits the concertinaed sausage casing to be held between the conveyor belt and the centering device. The apparatus includes a second permanent, magnet-excited dc motor to drive the conveyor belt and to further displace the sausage casing in the direction of the filling tube. Additionally, the apparatus has its own drive for adjusting the height of the centering device. The numerous drives with power and control signal cables poses a problem particularly in the foodstuffs industry, by virtue of hygiene requirements.
Therefore the object of the present invention is to provide an apparatus for gripping a sausage casing, in particular a gathered concertinaed sausage casing for a filling machine, which can be operated irrespectively of the diameter of the sausage casing and which can be easily driven and controlled.